Beispiel #1
0
// Open opens the named DB file for reading/writing. If successful, methods on
// the returned DB can be used for I/O; the associated file descriptor has mode
// os.O_RDWR. If there is an error, it will be of type *os.PathError.
//
// For the meaning of opts please see documentation of Options.
func Open(name string, opts *Options) (db *DB, err error) {
	defer func() {
		lock := opts.lock
		if err != nil && lock != nil {
			n := lock.Name()
			lock.Close()
			os.Remove(n)
			db = nil
		}
		if err != nil {
			if db != nil {
				db.Close()
				db = nil
			}
		}
	}()

	if err = opts.check(name, false, true); err != nil {
		return
	}

	f, err := os.OpenFile(name, os.O_RDWR, 0666)
	if err != nil {
		return
	}

	filer := lldb.Filer(lldb.NewSimpleFileFiler(f))
	sz, err := filer.Size()
	if err != nil {
		return
	}

	if sz%16 != 0 {
		return nil, &os.PathError{Op: "dbm.Open:", Path: name, Err: fmt.Errorf("file size %d(%#x) is not 0 (mod 16)", sz, sz)}
	}

	var b [16]byte
	if n, err := filer.ReadAt(b[:], 0); n != 16 || err != nil {
		return nil, &os.PathError{Op: "dbm.Open.ReadAt", Path: name, Err: err}
	}

	var h header
	if err = h.rd(b[:]); err != nil {
		return nil, &os.PathError{Op: "dbm.Open:validate header", Path: name, Err: err}
	}

	db = &DB{f: f, lock: opts.lock, closed: make(chan bool)}
	if filer, err = opts.acidFiler(db, filer); err != nil {
		return nil, err
	}

	db.filer = filer
	switch h.ver {
	default:
		return nil, &os.PathError{Op: "dbm.Open", Path: name, Err: fmt.Errorf("unknown dbm file format version %#x", h.ver)}
	case 0x00:
		return open00(name, db)
	}

}
Beispiel #2
0
// Open opens the named DB file for reading/writing. If successful, methods on
// the returned DB can be used for I/O; the associated file descriptor has mode
// os.O_RDWR. If there is an error, it will be of type *os.PathError.
//
// Note: While a DB is opened, it is locked and cannot be simultaneously opened
// again.
//
// For the meaning of opts please see documentation of Options.
func Open(name string, opts *Options) (db *DB, err error) {
	opts = opts.clone()
	opts._ACID = _ACIDFull
	defer func() {
		lock := opts.lock
		if err != nil && lock != nil {
			lock.Close()
			db = nil
		}
		if err != nil {
			if db != nil {
				db.Close()
				db = nil
			}
		}
	}()

	if err = opts.check(name, false, true); err != nil {
		return
	}

	f, err := os.OpenFile(name, os.O_RDWR, 0666)
	if err != nil {
		return
	}

	filer := lldb.Filer(lldb.NewSimpleFileFiler(f))
	sz, err := filer.Size()
	if err != nil {
		return
	}

	if sz%16 != 0 {
		return nil, &os.PathError{Op: "kv.Open:", Path: name, Err: fmt.Errorf("file size %d(%#x) is not 0 (mod 16)", sz, sz)}
	}

	var b [16]byte
	if n, err := filer.ReadAt(b[:], 0); n != 16 || err != nil {
		return nil, &os.PathError{Op: "kv.Open.ReadAt", Path: name, Err: err}
	}

	var h header
	if err = h.rd(b[:]); err != nil {
		return nil, &os.PathError{Op: "kv.Open:validate header", Path: name, Err: err}
	}

	db = &DB{f: f, lock: opts.lock}
	if filer, err = opts.acidFiler(db, filer); err != nil {
		return nil, err
	}

	db.filer = filer
	switch h.ver {
	default:
		return nil, &os.PathError{Op: "kv.Open", Path: name, Err: fmt.Errorf("unknown/unsupported kv file format version %#x", h.ver)}
	case 0x00:
		if _, err = open00(name, db); err != nil {
			return nil, err
		}
	}

	db.root, err = lldb.OpenBTree(db.alloc, opts.Compare, 1)
	db.wal = opts.wal
	return
}